Magnetic X-Y Coordinate Grid.

https://www.amazon.com/EAI-Education-Jumbo-Magnetic-Coordinate/dp/B01M3MMO6E

Our math department supplies students with individual white boards that have a graph on one side. By using this wall-mounted, magnetic coordinate plane, TMS math teachers can ensure students are learning individually as well as a class. The grid can also easily move among all math classes.